Duffy (heel) went 0-for-2 and played shortstop Saturday for High-A Charlotte, Bryan Levine of the Charlotte Sun reports.
Duffy sat out Friday's tuneup work, as he felt soreness in his surgically repaired heel during his Thursday contest. He came through on his expected plan by suiting up Saturday -- looking good at shortstop, per Levine -- though he failed to take a third at-bat because it "might've been doing more harm than good." That gives the impression his rehab work will go slowly. A late-May return looks plausible, either way.